CVE-2026-64106 KVM: arm64: vgic-its: Reject restored DTE with out-of-range num_eventid_bits
A flaw in the Linux kernel's KVM arm64 vgic-its allows a local attacker to cause a denial of service by restoring a device table entry with invalid event ID bits.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-64106?
CVE-2026-64106 is a critical denial of service vulnerability in Linux kernel, published on 19 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: vgic-its: Reject restored DTE with out-of-range num_eventid_bits
Userspace can restore an ITS Device Table Entry whose Size field encodes more EventID bits than the virtual ITS supports. The live MAPD path rejects that state, but vgic_its_restore_dte() accepts it and stores the out-of-range value in dev->num_eventid_bits.
Reject restored DTEs with num_eventid_bits > VITS_TYPER_IDBITS before allocating the device. This mirrors the MAPD check and prevents the restored state from reaching vgic_its_restore_itt(), where the unchecked value can be converted into an oversized scan_its_table() range.
Weakness: CWE-20
Which versions are affected by CVE-2026-64106?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-64106?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-64106 being exploited?
There is no known exploitation of CVE-2026-64106 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-64106, DEBIAN-CVE-2026-64106, GHSA-gf7v-gpf5-6fgc, ROOT-OS-DEBIAN-11-CVE-2026-64106, ROOT-OS-UBUNTU-2204-CVE-2026-64106, UBUNTU-CVE-2026-64106.